By the use of gel electrophoresis methods and devices, various molecular species such as proteins, and deoxyribonucleic acids (DNA) can be separated by charge and molecular weight. The gels are in the form of either slab or tube and are developed by methods involving silver stains or fluorescent dyes to visualize the migration of various species. The staining or dyeing processes require the exchange of solutions according to different stages of development which usually involves fixing, staining, and rinsing. The gels being composed of polyacrylamide or agarose are fragile and require extreme care when developing. As to avoid tearing or damaging the gels, efforts are made to avoid direct hand contact of the gels. Current manual methods employ a receptacle/tank to develop the gel aided by the use of a plastic scooper to transfer and hold the gel when exchanging the solution. The gels are frequently damaged during development and transfer using a scooper. Gel developing apparatuses such as U.S. Pat. No. 4,750,506 avoids direct handling of the gels by the use of cassettes to hold the gel within an outer tank. The problem lies with the cassettes which are intended to hold the gels in a vertical position during development. Gravity can cause the gels to slide down and lie undesirably folded at the bottom of the cassette. Furthermore, the cassettes equipped with the fluid permeable mesh to hold the gels in place require the gels to be of a certain thickness; too thick and the mesh can cause damage on the gel surface, too thin and the gel can slide down and fold up at the base of the cassette. The stacking arrangement of the cassettes also impairs visual monitoring of the gels. A gel destaining apparatus disclosed in U.S. Pat. No. 4,702,266 places gels in between horizontally stacked trays. For the purposes of destaining, the gels within do not have to be chronically monitored, however, for the purposes of gel staining and development, this stacking arrangement would greatly impair and obstruct visualization of the gels. A dish washing apparatus disclosed in U.S. Pat. No. 898,354 uses a submergible inner tray with openings for holding dishes within the outer tank. This inner tray functions to hold dishes within the closed dish washing apparatus. Furthermore, the base of the tray is not detachable and the apparatus is intended more towards washing dishes and not developing fragile electrophoresis gels. A tool decontamination apparatus disclosed in U.S. Pat. No. 4,630,625 has an inner chamber with openings along the floor. This inner chamber is positioned within the cabinet near the opening by the means of latches. Again, the inner chamber does not have a removable base and the chamber is positioned to facilitate a washing process with unwanted debris exiting through the openings and settling at the base of the cabinet.
Two other gel developing apparatuses claimed in U.S. Pat. No. 5,112,957 and 4,391,689 involve sophisticated systems which automatically dispense fixing, staining, and rinsing solutions as well as monitoring the development time. Such automated systems are expensive and arguably cumbersome for developing gels that require manual attention.
The present invention relates to an apparatus and method to develop gels efficiently with minimal contact of the gels of interest. The multi-tank gel developing apparatus can develop multiple gels in separate inner tanks which have openings above the base along the side walls which allow circulation of fluids with the inner and outer tanks. By lifting the inner tanks out and above the outer tank, the solution within the inner tanks can be drained. The remaining solution in the outer tank can be decanted and exchanged with a new solution. Afterwards, the inner tanks holding the gels of interest can be re-immersed into the outer tank for further processing and development.